Bottom-up synthesis of high-performance nitrogen-enriched transition metal/graphene oxygen reduction electrocatalysts both in alkaline and acidic solution. Issue 35 (18th August 2015) - Lai, Qingxue
Abstract : A versatile bottom-up protocol towards the synthesis of N–TM/G oxygen reduction electrocatalysts with a strongly-coupled triple junction structure is demonstrated. Abstract : Oxygen reduction electrocatalysts with low cost and excellent performance are urgently required for large-scale application in fuel cells and metal–air batteries. Though nitrogen-enriched transition metal/graphene hybrids (N–TM/G, TM = Fe, Co, and Ni and related compounds) have been developed as novel substitutes for precious metal catalysts (PMCs) towards oxygen reduction reaction (ORR), a significant challenge still remains for simple and efficient synthesis of N–TM/G catalysts with satisfactory electrocatalytic behavior. Herein, we demonstrate a universal bottom-up strategy for efficient fabrication of strongly-coupled N–TM/G catalysts. This strategy is implemented via direct polymerization of transition metal phthalocyanine (TMPc) in the two-dimensional confined space of in situ generated g-C3 N4 and a subsequent pyrolysis. Such a space-confined bottom-up synthesis route successfully constructs a strongly-coupled triple junction of transition metal–graphitic carbon–nitrogen-doped graphene (TM–GC–NG) with extensive controllability over the specific surface area, nitrogen content/types as well as the states of metal. As a result, the optimized N–Fe/G materials have promising potential as high-performance NPMCs towards ORR both in alkaline and acidic solution.